Several slight variations on this one; trying to see which timing works better!
First, general changes. As stated previously I've slightly altered the arc of the bounce. I think it's looking a lot better now! I also kept the ball stuck to the ground for just one frame before it bounces back up again. I had to alter the last (tiny) bounce in order to stop it looking too jerky - I had to increase the height of the ball very slightly and allow it enough time to come back down so that it wouldn't look like a weird juddery glitch, whilst still being quick enough to give the impression that it's barely more than a vibration. I don't know if I succeeded...!
The first thing I noticed was that the bounce itself was still slightly bothering me. With the new arc, it seemed even less weighty than before. It seemed to move too smoothly through the arc - it was a little too uniform. So I tried to increase the spacing between the impact with the ground and the first frame of the bounce, hoping that if it was a little faster it would appear to have struck the floor with more force.
With the new timing, I think the ball certainly "feels" heavier as it bounces off the floor, but the drop from the bounce seems too slow. I think maybe I got it backwards and should use the timing for the climb for the drop, and revert the climb back to its original speed? I decided to try doing the same thing for the drop's timing as well.
As I suspected, though, it made the whole thing too choppy. The ball is hardly in the air at all and it really needs to "hover" there for just a second as it fights against gravity.
I think I'll try reversing what I did for 7.2 - having the ascension of the bounce at the slower speed and the decline faster and see how it looks...